Tuesday 14 April 2009 17.37 EDT
First published on Tuesday 14 April 2009 17.37 EDT

America is facing a bed bug outbreak of explosive proportions - and the resistance of the blood suckers to commonly used pesticides means there is no magical cure, public health and pest control experts warned today.

Bed bug outbreaks in the US have tripled since 2005, a conference put on by the Environmental Protection Agency was told.

"It's become a trajectory. We are at the point similar to the Aids virus where everyone knows someone who has had bed bugs or have had it themselves," said Dini Miller, the urban pest management specialist for the state of Virginia.

"Right now we are kind of at a loss at what the best answer is," she said. "We didn't realise how tough they would be."

The EPA gathered experts in entomology and pest control as well as government officials to a two-day conference designed to chart a new strategy for dealing with a sudden and bewildering rise in bed bug infestations that has cut across class and region, affecting poor urban neighbourhoods and luxury resort hotels from New York City to Honolulu.

Bed bugs were once thought eliminated in the US. The conference - or summit as billed by the EPA - was told their return after nearly half a century was due to changes in pesticide use and increased resistance to pesticides by the bed bugs, as well as increased travel.

The move away from DDT towards less toxic and more targeted chemicals left America exposed to the return of their scourge. Earlier pesticides killed a broad range of insects. While they might have been marketed for cockroaches, they also wiped out bed bugs and other pests.

That left relatively few available formulations designed specifically for bed bugs. The narrow range made it easier for the bugs to build up resistance.

"Generally I can guarantee that they will be tolerant to at least one or more of the things that are being used against them," said Harold Harlan, the leading bug expert for the US military. "They've been exposed to chemicals so they are more resistant to chemicals."

Bed bugs do not transmit disease, but the bites can become infected – which they do in about 30% of those bitten, leaving them scratching red raised welts.

The tiny reddish-brown insects were once practically unheard of in the US. In the late 60s university entomologists were complaining about the scarcity of research samples. But by 2004, the bed bugs were back.

Since 2005, bed bug outbreaks have tripled across America, according to a survey of 800 pest control firms across the country. Bed bug control now makes up a rapidly rising share of the business.

In the north-eastern United States, especially New York City, pest control companies now make 9% of their earnings from trying to clear out bed bugs, Bob Rosenberg of the National Pest Management Association told the conference.

The scourge has also spawned its own subculture of victims, or more properly hosts.

The bitten, who may once have kept quiet out of shame, are turned activists, setting up tracking outbreaks, and personal accounts of infected bites and other horrors.

The infestations have gone beyond New York, with regular and persistent outbreaks reported in Honolulu, San Francisco, Cincinnati, Chicago, Houston and Miami. They are also concentrated in poor neighbourhoods, where people can not afford to call in the exterminators or to replace or professionally clean bedding and soft furnishing.

Commercial poultry farms, especially those where birds are allowed to roam around the hen house floor, are another newly discovered source.

Pesticides alone are unlikely to wipe the bed bugs out - and it's unrealistic to expect all those affected to treat or destroy infested furnishings. That means Americans can expect to co-habit with bed bugs for some time.

"The fact that we got rid of them for 50 years in the United States is now looking miraculous," she said.